/* 
 * [New BSD License (BSD 3-Clause License)]
 * Copyright (c) 2012, Max Bechtold
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * 
 *     - Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     - Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *     - Neither the name of the Rel2Xml Project nor the
 *       names of its contributors may be used to endorse or promote products
 *       derived from this software without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package maxbe.rel2xml.generator.docs.constraints;

import java.math.BigDecimal;
import java.math.RoundingMode;
import java.util.ArrayList;
import java.util.List;
import java.util.Random;

import maxbe.rel2xml.generator.docs.DataType;

import org.apache.log4j.Logger;

/**
 * Class for generating decimal values
 * 
 * @author Max Bechtold
 * 
 */
public class Decimals implements ValueConstructor {

	private Logger log = Logger.getLogger(Decimals.class);

	private static final List<DataType> types;

	private BigDecimal minValue;
	private BigDecimal maxValue;

	private static long seed = 277369899;
	private Random rand;

	private int scale;

	static {
		types = new ArrayList<DataType>();
		types.add(DataType.DECIMAL);
	}

	public Decimals(String dec1, String dec2) {
		try {
			minValue = new BigDecimal(dec1);
			maxValue = new BigDecimal(dec2);
			scale = minValue.scale();
			if (maxValue.scale() > scale)
				scale = maxValue.scale();
		} catch (Exception e) {
			log.error(e);
		}
		rand = new Random(seed++);
	}

	@Override
	public void announce(int number) {
		// Ignore
	}

	@Override
	public int getLength() {
		int length = minValue.toPlainString().replace("-", "").indexOf('.');
		int length2 = maxValue.toPlainString().replace("-", "").indexOf('.');
		if (length > length2)
			return length + scale;
		else
			return length2 + scale;
	}

	@Override
	public int getSubLength() {
		return scale;
	}

	@Override
	public List<DataType> getSupportedDataTypes() {
		return types;
	}

	@Override
	public boolean lengthVaries() {
		return false;
	}

	@Override
	public void mark(int number) {
		// Ignore
	}

	@Override
	public boolean needsAnnounce() {
		return false;
	}

	@Override
	public String next() {
		double d = rand.nextDouble()
				* (maxValue.doubleValue() - minValue.doubleValue())
				+ minValue.doubleValue();
		return new BigDecimal(d).setScale(scale, RoundingMode.HALF_UP)
				.toPlainString();
	}

	@Override
	public List<String> next(int number) {
		ArrayList<String> result = new ArrayList<String>(number);

		for (int i = 0; i < number; i++) {
			double d = rand.nextDouble()
					* (maxValue.doubleValue() - minValue.doubleValue())
					+ minValue.doubleValue();
			result.add(new BigDecimal(d).setScale(scale, RoundingMode.HALF_UP)
					.toPlainString());
		}
		return result;
	}

	@Override
	public String toString() {
		return String.format("decimal within [%s, %s]",
				minValue.toPlainString(), maxValue.toPlainString());
	}

}
